MICROSOFT_PRESS_EBOOK_PROGRAMMING_WINDOWS_8_APPS_WITH_HTML_CSS_AND_JAVASCRIPT_PDF

invoke the Settings charm. This is done through the settings pane object returned from
Windows.UI.ApplicationSettings.SettingPane.getForCurrentView, whose show method display
the UI (or throws a kindly exception if the app is in snapped view or doesn’t have the focus, so don’t
invoke it under those conditions!). The edge property of the settings pane object also tells you if it’s on
the left or right side of the screen, depending on the left-to-right or right-to-left orientation of the
system as a whole (a regional variance).
And with that we’ve covered all the methods and properties of this object! Yet the most interesting
part is how we add our own commands to the settings pane. But let’s first look at the guidelines for
using Settings.
Design Guidelines for Settings
Beyond the commands that Windows automatically adds to the settings pane, the app can provide up
to eight others, typically around four; anything more than eight will throw an exception. Because
settings are global to an app, the commands you add are always the same: they are not sensitive to
context. To say it another way, the only commands that should appear on the settings pane are those
that are global to the app; commands that apply only to certain pages or contexts within a page should
appear on the app bar or on the app canvas. Some examples of commands on the top-level settings
pane are shown in Figure 8-2.
FIGURE 8-2 Examples of commands on the top-level settings pane. Notice that the lower section of the pane always
has system settings and the app name and publisher always appear at the top. Permissions and Rate and Review are
added automatically.
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